Electric motors typically include a rotor and a stator. An electric motor stator typically has a plurality of fingers with copper wire wound about the fingers. Electric current flowing through the copper windings causes the rotor to rotate within the stator.
Copper windings in an electric motor must be insulated from the stator, which is typically made of metal. This insulation is normally a bobbin made of dielectric material. The bobbin is placed about the stator finger and the wire coil is wound about the bobbin.
Normally, electric motor insulating bobbins have a pair of opposing flanges connected by a tube which is an endless winding surface. The wire coil is wound about the winding surface of the bobbin between the opposing flanges. Insulating bobbins are made of a dielectric material which can withstand heat produced by the electric motor without melting or otherwise degrading. Paper products and dielectric polymers are used to form insulating bobbins.
Normally, it is desirable to maximize the horsepower produced by a given size electric motor. The greater amount of copper winding in an electric motor, the greater the horsepower produced by the motor. Thus, it is desirable to pack as much copper winding as possible in a given size electric motor. One way of providing more room in an electric motor is by using a thin bobbin. Thin polymer bobbins are made with injection molding techniques to have a thickness as low as about 35 mils. Nevertheless, a thinner polymer bobbin is desirable to produce electric motors having even higher horsepower output for a given size motor.